XT600 Swing Arm 'Stiff'
 

Hi - I lurk around here a lot and it helps greatly thanks. I'm rebuilding a 3TB 1991 (slowly).... so to the question:

I've removed the swingarm and linkage, replaced bearings and bushes packed with grease and reinstalled and torqued (no rear shock yet) and there's no sideways play but it seems stiff to 'waggle' up and down. No real effort required, but with it up in the air, the swingarm will not drop to the floor of its own accord (which it did prior to new bearings etc). Is this right? It doesn't strike me as a great problem as the shock and rear wheel should keep all in order but I guess I was expecting a looser rotation.

Cheers
Jim

hmmmm.

Did you install all the bushes and bearings correctly ? If you didn't drive the bearings in carefully and straight you could have damaged the cages. You could have also not squarely seated a bush. If there was a lot of corrosion before you changed them and didn't clean it out properly, it could cause this too.

I would try and see if the stiffness is in the swing arm or the linkage. Maybe loosen the nuts a little at a time on each joint and see if it eases up.

You would have to be a gorilla to over tighten these bolts so I don't think it's that.

However.. New bearings and bushes can be tight and often just need a bit of bedding in. Like you said, you can move them by hand so I don't think it's terminal yet.

I'd put it together and ride it a bit to let things settle in and then recheck.

Yeah, I think I seated everything correctly and got the bearings in properly. I believe I cleaned out all the corrosion - anything looking too bad was replaced when it came to bushes particularly.

Thanks for your thoughts, I think isolating to the swingarm or linkage is the first thing, so I'll go down that road.

Cheers
Jim.

So I narrowed this down to the swing arm pivot. If it's tightened up to the recommended 61ft lb it seems really stiff and I have to manually move it up and down. If I back it off to about 30ft lbs it behaves as I would expect - lift it up and let go and it hits the floor (or it would...).

I've tightened it up for now but if anything obvious jumps out at anyone, do shout up!

Thanks
Jim

hi did you fit any shims? , http://www.cmsnl.com/yamaha-xt600ebc...2.html#results ,items 7 or 49,they call it a washer plate but I would think its a shim ,steve

hi again heres another reference http://www.horizonsunlimited.com/hub...brations-42738 ,steve

sounds like somethng is binding

are you sure that when you are at only 30 of torque its not the spindle itslef that roatates?

Yep - I have a wrench in the other hand holding it fast.

I think you may have spotted it. This seems very similar. I have item 7 in, but on reflection I don't recall 49. And I'm not sure I put them in the right place - I found the diagram confusing....that parts fiche looks clearer.

Does anyone have the dimensions of part 49? I'll see if my local shop has something...

I'll try and report back - thanks a bunch.

I'm still having problems with this. It's binding when the frame tightens against the arm. I don't understand where to put the shims - my photo attached shows two yellow arrows where the item number 7 from above mentioned parts fiche page C8 is located. This is between the thrust cover and swingarm with the seal over the top. Same on both sides. The red arrows show a gap (through which I can see the bushes). My question is do I put shims where the red arrows point? Or somewhere else? and are the items number 7 in the right place? I'm really trying to learn about this so I can maintain my own bike. Much appreciate any help.

hi are the 2 collars items 2 and 3 Yamaha Xt600eb 1991 Crankcase - schematic partsfiche ,in place in the crankcases where the swinging arm spindle passes through ,on other bikes ive had the shims went between the swinging arm end cap and the thrust bearings to preload the thrust bearings , to take any slack out, yours seem to need loosing ,if the bushes were longer it might work ,try finding a washer the same od and id as the bushes ,put it in and torque everything up and see if that makes a differance,steve

OK cheers, will check it out later.